As a Roblox developer, it is currently too hard, if not impossible to make completely 2D games that don’t run like garbage.
I believe that if Roblox were to make 2D games a viable option for developers, we would see amazing retro games as well as modern indie games similar to Enter the Gungeon and Undertale on Roblox. Lots of retro indie games these days are made using a 2D engine, and I think that if a solid 2D engine were added that some of those 2D developers would come over to Roblox at some point. An example of a big name in game development coming to Roblox is Jamie Fristrom and his game Castleheart. If developers were given the tools to create full fledged 2D games, we would see some devs like that come over to Roblox.
It would be amazing to see a cool 2D platformer like Super Mario Bros, an adventure game like Zelda, or even a fast-paced platformer like Sonic the Hedgehog. Really, adding a 2D engine just expands the creativity on Roblox to a whole other dimension. Literally.
Edit: I forgot to mention that Unity has this feature and it makes Unity a lot more viable for all sorts of developers. Roblox could do the same.
While I would like the ability to make 2D games (like a lot please consider giving better tools for 2d games), I don’t think it would be in the interest of roblox to do so. It feels like it would take away lots of user customization and not feel like roblox to the player anymore, something roblox values because they make a lot of money from the catalog from users wanting to customize their characters. (There’s a reason custom character games are rarely on the front page)
It seems like too much hassle for not enough payoff and something they probably wouldn’t even consider.
Also, you can make 2D games already it just takes a little bit of knowledge about guis:
Examples:
This seems like a pretty baseless assertion. Given that Roblox is predominately a social platform and games where people can interact with each other are the most popular (I won’t give examples lol, the entire front page is the example). Only exceptions are Roses and Anxiety, which aren’t huge. I wouldn’t want Roblox to develop tools specifically for single player.
You can keep the 3D world, but force 2D physics with constraints and body objects, and you can change the core control/camera scripts as needed to make your game feel like 2D. (or 2.5D, at that point) 2.5D has the benefit that you can use the entire range of 3D objects in the Library, you can use stock special effects (particles/trails/etc) and you can also use players’ actual avatars, which you cannot if your game is just fully 2D.
If you really want it to be 2D, one solution you can try is to adorn UI objects to these 3D hitboxes to make it seem like they’re flat, but still the collisions are being calculated in 3D as well as the character being simulated in 3D. You don’t have to implement physics, replication, etc yourself that way, but you still get a 2D look.
Another solution is to look at open source 2D physics systems implemented in Lua, such as in Love2D’s open source engine. You can copy paste code from there to make a 2D physics system with UI. You will still need to implement replication and physics ownership yourself though, and simulating this in pure Lua might be a bit slow, so I don’t recommend this too much.